Vortex Movies

Defect sites are indicated by open circles, vortices are
shown as filled dots, and the paths followed by the vortices
are indicated by lines. As the magnetic field outside the
sample is increased, vortices enter the sample from the
left edge of the frame. The vortices follow interstitial
paths which move around regions with flux lines that are
strongly pinned at defects.

The weaker pinning in this sample produces a different manner
of vortex transport. Pin-to-pin vortex motion, as well as
interstitial motion, is possible and the previously narrow
vortex trails become considerably broader.

The left panel of the movie shows the averaged flux density as
the magnetic field outside the sample is increased; the right
panel shows the actual vortex locations. Vortices
enter the sample from the bottom of the figure. The sample
contains a single twin boundary which acts as an easy-flow
channel for flux motion. Vortices escape from the twin boundary,
producing the flame pattern.